At no time in history has a society possessed so much knowledge relevant to securing the health, safety, and prosperity of its members. Yet never has the content of what is collectively known-- from the reality of climate change to the efficacy of the HPV vaccine, from the impact of gun control on crime to the impact of tax cuts on public revenue--been a source of more intense and persistent political conflict.

We live in a liberal democratic society. We are thus free of the violent sectarian struggles that have decimated human societies from the beginning of history, and that continue to rage in those regions still untamed by the pacifying influence of doux commerce.

Yet we remain spectacularly factionalized—not over whose conception of virtue will be forcibly imposed on us by the state, but over whose view of the facts will be credited in the democratic processes we use to promulgate policies aimed at securing the wellbeing of all.

This is Popper’s Revenge—a tension inherent in, and potentially destructive of, the constitution of the Liberal Republic of Science.

In the first of this series of posts on the Liberal Republic of Science, I identified what sort of thing the Liberal Republic Science is: a political regime, or collective way of life animated by a foundational set of commitments that shape not only its institutions of government but also its citizens’ habits of mind and norms of engagement across all domains of social and private life.

In the second, I described the Liberal Republic of Science’s animating idea: the mutually supportive relationship of political liberalism and scientific inquiry. In The Logic of Scientific Discovery, Popper identifies science’s signature way of knowing with the amenability of any claim to permanent empirical challenge. The vitality of this distinctive mode of inquiry, in turn, presupposes Popper’s Open Society: only in a state that disclaims the authority to orchestrate collective life in pursuit of rationally ascertained, immutable truths will individuals develop the disputatious and inquisitive habits of mind, and society the competitive norms of intellectual exchange, that fuel the scientific engine of conjecture and refutation.

The cultural polarization we today observe over risks and how to abate them, I now want to argue, is in fact a byproduct of the very same characteristics that make a liberal society conducive to the acquisition of scientific knowledge.

Obviously, the collective knowledge ascertained by science will far exceed what any individual (layperson or scientist) can hope to understand much less verify for him- or herself. As a result, there must be reliable social mechanisms for certifying and transmitting what’s known to science--that is, for certifying and transmitting what’s known to us collectively through science’s signature mode of inquiry.

Popper himself recognized this. He mocked (gently; he was not ungrateful to the nation that saved him from National Socialism) English sensory empiricism, which asserts that first-hand observation is the only valid foundation for knowledge. What enables the members of a liberal democratic society to participate in the superior knowledge that science conveys is not their “refusal to take anyone one’s word for it” (nullius in verba, the motto of the Royal Society) but rather their reliance on the words of those who will reliably certify as “true” only those claims originating in the use of science’s distinctive mode of knowing.

In a liberal society, however, there will always be a plurality of such truth certifiers. People naturally acquire their personal knowledge of what’s collectively known within a cultural community, whose members trust and understand each other. The citizens of the Liberal Republic of Science are culturally diverse—historically so. As the number of facts known to science multiplies, the prospect of disagreement among these plural systems of certification becomes a statistical certainty.

Such conflicts, moreover, feed on themselves. The conspicuous association between opposing positions and opposing groups transforms factual beliefs into emblems of identity. Policy determinations become referenda—not over the weight of the evidence in support of competing empirical claims but over the honesty and competence of competing cultural constituencies. Otherwise nonpartisan citizens are impelled to pick sides in what they are now constrained to experience as a “struggle for the soul” of their society.

As I explained in my last post, the nourishment that liberal political culture furnishes scientific inquiry is one half of Liberal Republic of Science’s animating idea. The other is the reciprocal nourishment that science furnishes the cultural of liberal democracy, whose citizens it thrills and inspires and teaches to think.

I acknowledged, too, at the end of the post, that many of you might question my suggestion that the U.S. is a Liberal Republic of Science, precisely because you might doubt my suggestion that the citizens of the U.S. are one in the view that science’s way of knowing is the best one. I surmised that you might perceive instead that the U.S. is in fact a “house divided” between those who want to perfect the Liberal Republic of Science and those who want to destroy it.

My claim now is that this very perception itself is part and parcel of Popper’s Revenge.

The conflict over climate change is not one between those who accept science’s way of knowing and those who don’t.

The conflict over nuclear power is not one between those who accept science’s way of knowing and those who don’t.

The conflict over the HPV vaccine, over guns, over GM foods—none of these is between those who accept science’s way of knowing and those who don’t.

But this last mistake is arguably the one that harms them the most. For it is the barrier that Popper’s Revenge puts in the way of their seeing that they are all citizens of the Liberal Republic of Science that obscures their apprehension of the interest they share in using the science of science communication to perfect this very defect in their political regime.

Research of the Cultural Cognition Project is or has been supported by the National Science Foundation; by the Woodrow Wilson International Center of Scholars; by the Arcus Foundation; by the Ruebhausen Fund at Yale Law School; the Edmond J. Safra Center for Ethics at Harvard University; Skoll Global Threats Fund; and by GWU, Temple, and NYU Law Schools. You can contact us here.